Ignition apparatus for large internal-combustion engines.



G. HONOLD. IGNITION APPARATUS FOR LARGE INTERNAL COMBUSTION ENGINES.

' APPLICATION IILED .TULY27, 190a.

- Patented Dec.17, 1912 I 2 SHEETS-SHEET 1.

WITNESSES Inn/ENTER GOTTLOB HONOLD, F STUTTGABT, GERMAIJ'Y.

IGNITION APPARATUS FOR LARGE INTERNAL- COMBUSTION ENGINES.

\ To all whom it may concern:

' Be it known that I, GOTTLOB HonoLn, en-

gineer, a subject of the German Emperor,

. residing at 11 Hoppenlaustrasse, Stuttgart,

Germany, have invented certain new and useful Improvements in Ignition Apparatus for Large Internal-Combustion Engines; and -I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

For the working of large internal com-' bustion engines it is desirable that the ignition in each cylinder should occur simultaneously at several places, in order that the combustion of the gaseous mixture may be more uniform and more rapid. The application of this idea by connecting up in series two or more high tension sparking plugs ofi'ers such great difficulties that experiments in this direction have notsucceeded. The high tension current has in this case to overcome not only the normal air resistance of the spark-gaps placed in series but also the resistance caused by the compression.- For example if the electrodes oftwo plugs in series have each a gap of 0.5 mm. then with a compression of 6 atmospheres a voltage sufiicient to bridge two air gaps of 6 mm. eachat atmospheric pressure is necessary. To insulate efliciently and continuously such an apparatus, especially as both ends of the coils must be insulated, is impracticable. Besides this, if the magneto or other source of electric current decrease in power in the'slightest degree, the voltage limit sufiicient to bridge the gap is soon reached. According to the present invention these disadvantages are removed by arranging in each cylin er two or more electromagnetically operated sparking plugs in series so that the compression has no effect on the formation of the spark and no difliculties occur as regards insulation. In this manner, as compared with high tension devices, eflfective sparks are obtained with certainty in all cases. If the plugs are connected up in series then the control of the 1gn1't1o'n device has tofulfil certain conditions, and is made possible with the connections to be hereinafter described.

' In the accompanying drawings, Figure 1 is a diagrammatic representation of the invention as applied to a single cylinder engme. Fig. '2 1s a similar view showing a Specification of Letters Patent.

Application filed July 27, 1908.

Patented Dec. 17, 1912.

Serial No. 445,597.

either a simple winding a as in Fig. 1 or a coil divided into halves a, and 06 as shown in Fig.- 2. In both these cases the coil ends insulated fromthe body are electricallyeonnected in a suitable manner by segments and .slip brushes, which if desired may act as throw over switches, with the leads of the sparking plugs d d and also with the two contact pieces-of an interrupter e operated by the engine shaft. This interrupter serves to short circuit the coil a, or a a which short circuit should not be broken until the moment of ignition.

In Figs. 1 and 2 the arrangement for a single cylinder motor is shown' diagrammatically, b, and 6 being the contact pieces or segments which rotate with the armature and 0, and o, the fixed contacts or brushes connected with the sparking plugs, The spark gap of each plugis in the samecylinder.

When there is more than one cylinder to fire, a distributer must be used in the usual manner. Fig.- 3 shows as an example such an arrangement for a two-cylinder motor, the cranks of which are rotatively displaced through 180. In all other cases various alterations are necessary but these are obvious and do not affect the essentials of the invention.

The reference letters in Fig. 3 are the same as those in Figs. 1 and 2. I and II are the two cylinders. The contact pieces (segments 12,, b rotating with 'the armature at the same velocity as the crank shaft are in this case 90 apart, and are connected respectively with the insulated ends of the armature winding and also with the interrupter contacts (2 respectively which also rotate.-

such a manner that ignition occurs first in cylinder I and then in cylinder II.;

The rotary interrupter e is of a well known type whose operation isWell understood, and therefore requires no further explanation, other than to say that the armature current is maintained closed through the contacts of the interrupter e," until the pivoted contact arm is moved by one of the cam blocks, as i to separate the contacts 6 so that the magneto current will then pass by way of segment 11,, and brush 0, to spark plug d, thence through-the metal of the engine cylinder to spark plug (l to brush 0,, segment 12, back to the armature of the magneto. Similarly in order to effect ignition in the cylinder II, the pivoted inemberof the interrupter 6 passes into engagement with the cam block 2', and interrupts the shunt circuit at the contacts of the inter .the combination with each cylinder, of 'a rupters so that the current flows directly fromthe magneto, by way of the segments 6,, b brushes c and 0,, through the spark plugs d, and a in series.

With double acting single cylinder motors whose two ignitionsareat one time displaced 180? at the other time 3x180, an arrangementsuch'as shown in Fig. 4 may be used. v

The distributer disk It rotates at'the same speed as the cam shaft, it being immaterial I whether the armatu c has the same speed or whether the speed of. the distributer is. re-

duced to one halfthat of the armature by intermediate gearing.- In this manner the '0' eration distributed over two complete revo utions of-the-motor canbe transferred to a revolution of the distributer. disk, so that one pair of contacts'c,, 0,, for the plugs (1,, (1,, .are at 90 to the second pair 0,, 0,,

" for the plugs d,,-'d,, thus causing ignition first in the cylinder space A then in the cylinder space B. Also in double acting inter.- nal combustion engines, the above described -arrangement can be adopted with suitable Having thus described the nature of invention and the best means I know of carrying the same into practical effect, I claim 1. In large internal combustion engines,

plurality of electromagnetically operated sparking plugs in series, a source of electric current, rotary contacts, conductively connected to the terminals of said source of electric current, means whereby the rotating contacts are brought into electrical connection with the said sparking plugs at the proper moment, and an interrupter.

2. In large internal combustion engines the combination with each cylinder, of a plurality of electromagnetically operated sparking plugs in series, a generating coil, rotary contacts connected to the terminals of said coil, means whereby the contacts are brought.

into electrical connection with the said sparking plugsat the proper moment, and

an interrupter.

In testimony where'ofI have afiixed my signature, in presence of two witnesses.

E. ULMER. 

